Process for the production of acrylamide and methacrylamide

ABSTRACT

Process for the production of acrylamide or methacrylamide wherein acrylonitrile or methacrylonitrile is reacted with water and/or a water donor in the presence of Raney copper catalyst, which is protected from contact with oxygen.

This is a continuation of application Ser. No. 70,516, filed on Aug. 28,1979, now abandoned, which is a continuation of application Ser. No.795,283, filed on May 9, 1977, now abandoned, which is a continuation ofapplication Ser. No. 56,967, filed on July 21, 1970, now U.S. Pat. No.4,056,565.

This invention relates to a process for the production of acrylamide ormethacrylamide wherein acrylonitrile or methacrylonitrile is hydrated.More particularly, this invention relates to a process for theproduction of acrylamide or methacrylamide wherein acrylonitrile ormethacrylonitrile is reacted with water and/or water donor in thepresence of a catalyst.

In recent years, acrylamide and methacrylamide have been heavily indemand as a paper reinforcing agent, soil solidifying agent, fibertreating agent, etc., and have become important chemicals. As theproduction of these compounds on a commercial scale was expensive, thereis a need for an economical process for the production of thesecompounds.

The object of the present invention is to provide a new process for theproduction of acrylamide and methacrylamide. It has now been found thatacrylonitrile or methacrylonitrile is reacted with water or a waterdonor in the presence of a catalyst containing Raney copper, Ullmancopper, reduced copper catalyst, copper having a carrier, silver, gold,cobalt, nickel, palladium and/or platinum, whereupon acrylamide ormethacrylamide is produced.

At present, a process for the production of acrylamide or methacrylamideon an industrial scale comprises first reacting acrylonitrile ormethacrylonitrile with sulfuric acid to form acrylamide sulfate ormethacrylamide sulfate and successively neutralizing the sulfate toseparate acrylamide or methacrylamide. According to this process,however, polymerization tends to take place during the production ofacrylamide sulfate or methacrylamide sulfate and the separation ofacrylamide or methacrylamide by successively neutralizing said sulfateis extremely difficult.

According to this invention, acrylamide or methacrylamide can easily beproduced economically by hydrating acrylonitrile or methacrylonitrilewithout using sulfuric acid.

The reaction according to this invention is considered to take place,for example, as shown below; ##STR1##

In this invention, it is most preferable to react acrylonitrile ormethacrylonitrile with water. However, acrylamide or methacrylamide canbe produced by employing acrylonitrile or methacrylonitrile and a waterdonor such as an alcohol, water-containing substance or a mixture ofhydrogen and oxygen. Water donors usable in this invention include,aliphatic monohydric alcohols such as methanol, ethanol, n-propanol,isopropanol, sec-butanol, tert-butanol, pentanol-2, pentanol-3,2-methylbutanol-3,4-methylpentanol-2, hexanol-2, hexanol-3, etc.;aliphatic dihydric alcohols such as hexylene glycol, butylene glycol,propylene glycol, ethylene glycol, etc.; alicyclic alcohols such ascyclohexanol, etc.; water-containing solvents; and a mixture of hydrogenand oxygen or of hydrogen and air.

In this invention, no special limitation is needed for the quantity ofwater or water donor used to react with acrylonitrile ormethacrylonitrile. Although acrylonitrile or methacrylonitrile reactswith even a very slight amount of water or water donor, the quantity ofacrylamide or methacrylamide produced from the starting acrylonitrile ormethacrylonitrile becomes larger as the quantity of water or water donorbecomes larger and is used in excess. Consequently, the quantity ofwater or water donor used is preferably 0.01-100 mols per mol ofacrylonitrile or methacrylonitrile.

Utilizable as catalysts in this invention are those catalysts containingRaney copper, Ullman copper, reduced copper catalyst, copper having acarrier, silver, gold, cobalt, nickel, palladium and/or platinum.

Usable as catalysts in this invention are said copper-containingcatalysts which further contain metals such as nickel, chromium,manganese, zinc, molybdenum, etc. and their oxides, sulfides, etc., Whensaid copper-containing catalyst is used in the reaction, the copper isnot substantially ionized in the reaction mixture.

The usable silver-containing catalysts include, for example, reducedsilver, silver oxide, powdery silver, spongy silver, silver having acarrier, silver oxide having a carrier, etc. Also usable aresilver-containing catalysts which further contain other metals such ascopper, nickel, chromium, zinc, etc., and their oxides, sulfides, etc.

The usable gold-containing catalysts include, for example, reduced gold,gold oxide, powdery gold, gold having a carrier, gold oxide having acarrier, etc. Also usable are gold-containing catalysts which furthercontain other metals such as silver, copper, nickel, chromium, zinc,etc., and their oxides, sulfides, etc.

The usable cobalt-containing catalysts include, for example, Raneycobalt, reduced cobalt, cobalt having a carrier, Urushibara cobalt,cobalt oxides, etc. The cobalt-containing catalysts which furthercontain other metals, oxides, sulfides, etc., are also usable.

The usable nickel-containing catalysts include, for example, Raneynickel, reduced nickel, nickel oxide, nickel having a carrier,Urushibara nickel, nickel formed by thermal decomposition of nickelformate, etc. The nickel-containing catalysts which further containother metals, oxides, sulfides, etc., are also usable.

The usable palladium-containing catalysts include, for example,palladium black, palladium oxide, colloidal palladium, palladium havinga carrier, etc. The palladium-containing catalysts which further containother metals, oxides, sulfides, etc., are also usable.

The usable platinum-containing catalysts include, for example, platinumblack, platinum oxide, colloidal platinum, platinum skeleton catalyst,platinum having a carrier, etc. The platinum catalysts which furthercontain other metals, oxides, sulfides, etc., are also usable.

The reaction proceeds even in the event that the amount of said catalystused in this invention is very small. For example, addition of saidcatalyst in an amount of 0.01 g. per mol of acrylonitrile ormethacrylonitrile is sufficient to make the reaction proceed. The largerthe amount of catalyst used, the faster the reaction proceeds, thuspermitting increase of the amount of acrylamide or methacrylamideproduced. Consequently, the amount of said catalyst is preferably0.01-100 g. per mol of acrylonitrile or methacrylonitrile.

The reaction according to this invention can be carried out by employingsaid catalyst in the form of a suspended bed and/or fixed bed.

When this invention is carried out using a suspended bed, two or morereactors are connected in series and the reaction liquid and thecatalyst are countercurrently moved to effect reaction. In this case,the phrases "the reaction liquid and the catalyst are countercurrentlymoved to effect reaction" is illustrated by the following operation: Inthe case of connecting "n" number of reactors in series, acrylonitrileor methacrylonitrile and water or water donor are supplied to the firstreactor, i.e., reactor No. 1, and the reaction liquid discharged fromreactor No. 1 is then fed into reactor No. 2. In such manner, reactionliquid discharged from reactor No. 2 is fed in consecutive order intoreactor No. "n". On the other hand, the catalyst is supplied to reactorNo. "n" where the reaction is carried out in such state that thecatalyst is suspended in the reaction liquid, while the catalystdischarged from reactor No. "n" is fed into reactor No. "n-1" where thereaction is carried out in the suspended state. Thus, the catalystdischarged from reactor No. "n-1" is fed in regular sequence intoreactor No. 1 to effect the reaction in the suspended state.

The reaction according to this invention is carried out at roomtemperature (25° C.) or at a temperature lower than room temperature.However, the reaction rate can be increased by elevating the reactiontemperature. If the reaction temperature is raised too high, sidereactions including polymerization of acrylonitrile or methacrylonitrilewill tend to take place. Addition of a polymerization inhibitor such ashydroquinone is effective to inhibit such side reactions. Even if thereaction temperature is raised to 200° C. or higher, acrylamide ormethacrylamide will be formed according to said reaction, but theoptimum temperature is within the range of 25°-200° C.

The reaction according to this invention proceeds easily underatmospheric pressure not only in air but also in nitrogen, oxygen,carbon dioxide, hydrogen or the like atmosphere. It is also possible toperform said reaction under superatmospheric pressure. The reaction isnot considerably affected by pressure but can be carried out under apressure of 0-300 kg/cm². The reaction according to this invention canbe carried out in either liquid phase or vapor phase.

In carrying out this invention, an organic solvent may be added to thereaction system. Solvents utilizable for this invention includemethanol, ethanol, isopropanol, acetone, dimethyformamide,dimethylsulfoxide, formamide, acetamide, etc. Addition of such solventto the reaction system permits, for example, increase of theconcentration of acrylonitrile or methacrylonitrile in water. Acrylamideor methacrylamide can previously be added as solvent to the reactionsystem to similarly increase the concentration of acrylonitrile ormethacrylonitrile.

The following advantages can be achieved by practicing this invention:First, in the known process using sulfuric acid for preparing acrylamideor methacrylamide from acrylonitrile or methacrylonitrile whereinpolymerization takes place with the violent evolution of heat, theremoval of heat and the addition of a polymerization inhibitor areneeded. In the process of this invention, however, such violentevolution of heat and polymerization virtually absent and the formationof by-products from acrylonitrile or methacrylonitrile is slight, thusmaking it possible to produce acrylamide or methacrylamide in anextremely high yield. Secondly, the process used in this invention forthe production of acrylamide or methacrylamide has a smaller number ofprocessing steps and permits the easy isolation of acrylamide ormethacrylamide as product. The known process employing sulfuric acid hasto include the neutralization of the resultant acrylamide sulfate ormethacrylamide sulfate and the separation of the sulfate formed byneutralization in order to obtain the acrylamide or methacrylamide.However, the achievement of such neutralization and separation isextremely difficult in operation and significantly adversely effects theeconomics of the production process. The process of this inventionnecessitates no neutralization and makes it easy to isolate theresultant acrylamide and methacrylamide. Thirdly, the quality of theproduct obtained according to the process of this invention isexcellent. In the known process wherein sulfuric acid, polymerizationinhibitor, neutralizing agent, etc., are used, it is very difficult toisolate acrylamide or methacrylamide in pure form.

This invention is illustrated in more detail by the following examples:

EXAMPLE 1

In a 100 ml. 4-necked flask was placed about 1 g. of Raney copper(Kawaken Fine Chemical, CDT-60) which had been developed and washed withwater and then with isopropanol, 30.0 g. of acrylonitrile and 13.3 g. ofisopropanol. Under atmospheric pressure, the mixture was refluxed withstirring for 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the catalyst was filtered off and thefiltrate was evaporated to obtain about 1.5 g. of a white crystallineproduct. The product was issolved in a mixture of diethyl ether andethanol and recrystallized therefrom to yield a white crystallineproduct having a melting point of 84.5°-85° C. This product wasidentified as acrylamide, from the results of gas chromatographicanalysis, elementary analysis, IR analysis and NMR analysis. Very smallamounts of acetone and an indeterminable substance were also obtained asby-products.

EXAMPLE 2

In the procedure described in Example 1, 1 g. of Raney copper which hadbeen developed and washed with water was further washed with ethanol andthe composition of the reaction liquid was 30.0 g. of acrylonitrile and10.0 g. of ethanol. The liquid was reluxed for 2 hours at a reactiontemperature of about 68° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 1.2 g. of acrylamide were obtained as the product.A small amount of an indeterminable substance was also obtained asby-product.

EXAMPLE 3

In the procedure described in Example 1, about 2 g. of Raney copperwhich had been developed and washed with water were subjected togetherwith a liquid mixture of 25.0 g. of water (separated into two layers) toreflux for 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 8.1 g. of acrylamide were obtained as the product.No by-product was found.

EXAMPLE 4

In the procedure described in Example 1, about 2 g. of Raney copperwhich had been developed and washed with water were used and a reactionliquid composed of 26.5 g. of acrylonitrile, 18.0 g. of water and 20.0g. of dimethylformamide was refluxed for 2 hours at a reactiontemperature of about 74° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 6.7 g. of acrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 5

In the procedure described in Example 1, about 2 g. of Raney copperwhich had been developed and washed with water were used and a reactionliquid composed of 26.5 g. of acrylonitrile, 18.0 g. of water and 15.0g. of isopropanol was refluxed for 2 hours at a reaction temperature ofabout 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 4.7 g. of acrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 6

In the procedure described in Example 1, about 2 g. of Ullmann copperwhich had been prepared by treating an aqueous solution of cupricnitrate with metallic zinc were used and a liquid mixture of 25.0 g. ofacrylonitrile and 25.0 g. of water (separated into two layers) was usedas the reaction liquid and was refluxed for 2 hours at a reactiontemperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 2.3 g. of acrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 7

In the procedure described in Example 1, a reduced copper catalyst wasused in place of the Raney copper. 125 Grams of cupric nitrateCu(NO₃)₂.3H₂ O were dissolved in 1500 ml. of water and the solution waswarmed to 80° C. A 20% aqueous solution of caustic potash was addeddropwise to the above solution until the pH became 9-10 to obtain cuprichydroxide. The resultant cupric hydroxide was washed well with warmwater until the washed solution became neutral and was then dried at100° C. 10 Grams of the resultant cupric hydroxide were charged into a100 ml. 4-necked flask and reduced for 2 hours at 170° C. with hydrogenat a flow rate of 300 ml./min. to prepare said catalyst. Into the flaskcontaining said reduced copper catalyst was poured a liquid mixture of25.0 g. of acrylonitrile and 25.0 g. of water and the mixture wasrefluxed for 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 4.2 g. of acrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 8

In the procedure described in Example 1, a copper asbestos catalyst wasused in place of the Raney copper. 15 Cubic centimeters of an aqueoussolution of cupric nitrate (4.2 g. as copper) were absorbed on 3 g. ofasbestos which had been boiled with nitric acid, washed with water andthen dried. The asbestos thus treated was added in portions to 50 cc ofa boiling aqueous solution of caustic soda, filtered, washed with waterand then dried. The asbestos was then charged into a 100 ml. 4-neckedflask and reduced for 2 hours at 260° C. with hydrogen at a flow rate of50 ml./min. to prepare said copper asbestos catalyst. Into the flaskcontaining the copper asbestos catalyst was poured a liquid mixture of25.0 g. of acrylonitrile and 25.0 g. of water and the mixture wasrefluxed for 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 3.6 g. of acrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 9

In the procedure described in Example 1, a copper-chromium catalyst wasused in place of the Raney copper. 10 Grams of copper-chromium oxidepowders containing a small amount of manganese oxide (Nikki Kagaku,Copper-chromium catalyst N203) were charged into a 100 ml. 4-neckedflask, reduced for 5 hours at 200° C. with hydrogen at a flow rate of150 ml./min. and then cooled to room temperature while allowing theintroduction of a hydrogen stream. Into the flask containing the reducedcopper-chromium catalyst was poured a liquid mixture of 25.0 g. ofacrylonitrile and 25.0 g. of water and the mixture was refluxed for 2hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 2.6 g. of acrylamide and a very small amount ofpropionitrile were obtained as the products. Substantially noby-products were found.

EXAMPLE 10

In the procedure described in Example 1, a copper-zinc catalyst was usedin place of the Raney copper. 10 Grams of a cylindrically shapedmaterial comprising copper oxide and zinc oxide (Nikki Kagaku,Copper-zinc catalyst N211) were crushed to a powder, charged into a 100ml. 4-necked flask, reduced for 2 hours at 300° C. with hydrogen at aflow rate of 100 ml./min. and then cooled to room temperature whileallowing the introduction of a hydrogen stream. Into the flaskcontaining the copper-zinc catalyst was poured a liquid mixture of 25.0g. of acrylonitrile and 25.0 g. of water and the mixture was refluxedfor 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 2.3 g. of acrylamide and a small amount ofpropionitrile were obtained as the products. Substantially noby-products were found.

EXAMPLE 11

In the procedure described in Example 1, 8.7 g. of Raney copper whichhad been developed and washed with water, 18.9 g. of acrylonitrile and81.1 g. of water were charged into an autoclave and reacted underagitation in nitrogen atmosphere for 130 minutes at a reactiontemperature of 120° C. During the reaction, the inner pressure waschanged from 3 kg./cm² to 1 kg./cm². After completion of the reaction,the results of gas chromatographic analysis showed that 25.0 g. ofacrylamide were obtained as the product. No by-product was found.

EXAMPLE 12

In the procedure described in Example 1, about 10 g. of Raney cobalt(Kawaken Fine Chemical, R-ODET-60) which had been developed and washedwith water were used as the catalyst and 3.3 g. of acrylonitrile and36.0 g. of water were refluxed under agitation in the presence of thecatalyst for about 2 hours at a reaction temperature of about 70° C.

After completion of the reaction, the results of gas chromatographicanalysis showed that 1.06 g. of acrylamide and a small amount ofpropionitrile were obtained as the products together with a very smallamount of an indeterminable substance.

EXAMPLE 13

In the procedure described in Example 1, a cobalt catalyst with acarrier was employed as the catalyst. In a 50 ml. 2-necked, confinedflask were placed 10 g. of a reduced stabilized cobalt-diatomaceousearch catalyst (Chemetron Corp.) The catalyst was heated and hydrogengas was introduced to effect reduction. In this case, the flow rate ofhydrogen was 50 ml./min., the reduction temperature was 800° C. and thereduction time was 2 hours. After reduction, the catalyst was cooled toroom temperature while allowing the introduction of a hydrogen stream.Introduction of the hydrogen stream was then stopped and a liquidmixture of 3.3 g. of acrylonitrile and 36.0 g. of water was poured ontothe catalyst in such manner that the catalyst was not brought intocontact with air.

The analysis results after the reaction showed that 0.37 g. ofacrylamide and a small amount of propionitrile were obtained as theproducts together with a very small amount of an indeterminablesubstance.

EXAMPLE 14

In the procedure described in Example 1, Raney nickel (Kawaken FineChemical, NDT-65) which had been developed and washed with water wasused and a liquid mixture of 3.3 g. of acrylonitrile and 36.0 g. ofwater was refluxed together with the catalyst for 2 hours at a reactiontemperature of about 70° C.

After the reaction, the catalyst was filtered off and the reactionmixture was subjected to gas chromatographic analysis. The analysisresults showed that 0.90 g. of acrylamide and a small amount ofpropionitrile were obtained as the products. No by-product was found.

EXAMPLE 15

In the procedure described in Example 1, a nickel catalyst with acarrier was used as the catalyst. In a 50 ml. 2-necked, confined flaskwere placed 10 g. of a stabilized nickeldiatomaceous earth catalyst(Nikki Kagaku N113; containing as cocatalyst a small amount of oxides ofcopper and chromium). The catalyst was heated and hydrogen gas wasintroduced to effect reduction. In that case, the flow rate of hydrogen,the reduction temperature and the reduction time were 100 ml./min., 200°C. and 2 hours, respectively. After completion of the reduction, thecatalyst was cooled to room temperature while allowing the introductionof a hydrogen stream. Introduction of the hydrogen stream was thenstopped and a liquid mixture of 3.3 g. of acrylonitrile and 36.0 g. ofwater was poured onto the catalyst in such manner that the catalyst wasnot brought into contact with air.

The analysis results after the reaction showed that 0.36 g. ofacrylamide and a small amount of propionitrile were obtained as theproducts. No by-product was found.

EXAMPLE 16

In the procedure described in Example 1, a catalyst prepared by reducing1.0 g. of 5% palladium carbon powder (Nihon Engerhalt) at 200° C. for 2hours with hydrogen at a flow rate of 50 ml./min. was used, and a liquidmixture of 6.6 g. of acrylonitrile and 36.0 g. of water was used as thereaction liquid and was refluxed for 5 hours at a reaction temperatureof about 70° C.

After the reaction, the catalyst was filtered off and the reactionmixture was subjected to gas chromatographic analysis. The analysisresults showed that 1.36 g. of acrylamide and a very small amount ofpropionitrile were obtained as the products together with a very smallamount of an ideterminable substance.

EXAMPLE 17

In the procedure described in Example 1, a catalyst prepared by reducing1.0 g. of 1% platinum carbon powder (Nihon Engerhalt) at 200° C. for 2hours with hydrogen at a flow rate of 50 ml./min. was used, and a liquidmixture of 6.6 g. of acrylonitrile and 36.0 g. of water was used as thereaction liquid and was refluxed for 5 hours at a reaction temperatureof about 70° C.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis. The analysisresults showed that 0.98 g. of acrylamide was obtained as the product.No by-product was found.

EXAMPLE 18

Using in the procedure described in Example 1, the experiment wasconducted using 0.5 g of palladium carbon as the catalyst and a mixtureof 3.3 g. of acrylonitrile and 36.0 of water as the reaction liquid.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 0.67 g. of acrylamide and a very small amount ofpropionitrile were obtained as the products together with a very smallamount of an indeterminable substance.

EXAMPLE 19

Using the procedure described in Example 1, the experiment was conductedusing 0.5 g of platinum black as the catalyst and a mixture of 3.3 g. ofacrylonitrile and 36.0 g. of water as the reaction liquid.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 0.52 g. of acrylamide was obtained as the product. Noby-product was found.

EXAMPLE 20

10 Grams of a silver oxide catalyst on an alumina carrier (1% Ag₂ O;Toyo CCI) were placed in a 100 ml. 4-necked flask and reduced at 200° C.for 2 hours with hydrogen at a flow rate of 50 ml./min. to prepare acatalyst. Into the flask containing said catalyst was poured a mixtureof 6.6 g. of acrylonitrile and 36.0 g. of water and the whole wasrefluxed for 2 hours at a reaction temperature of about 70° C.

After the reaction, the catalyst was filtered off and the filtrate wasevaporated to yield 0.85 g. of a white crystalline product. The productwas dissolved in a mixture of diethyl ether and ethanol andrecrystallized therefrom to obtain a white crystalline product having amelting point of 84.5°-85° C. This product was identified as acrylamide,based upon the results of gas chromatographic analysis, elementaryanalysis, IR analysis and NMR analysis. Very small amounts of ethylenecyanohydrin and propionitrile were obtained as by-products.

EXAMPLE 21

In the procedure discribed in Example 20, 20 g. of the silver oxidecatalyst on alumina carrier were reduced and charged into an autoclave,and 13.2 g. of acrylonitrile and 72 g. of water were then chargedthereinto and reacted for 2 hours at a reaction temperature of 150° C.under agitation in a hydrogen atmosphere.

After completion of the reaction, the results of gas chromatographicanalysis showed that 5.85 g. of acrylamide and 2.86 g. of ethylenecyanohydrin were obtained as the products together with a very smallamount of an indeterminable substance.

EXAMPLE 22

Except that unreduced silver oxide catalyst on alumina carrier was usedin the procedure described in Example 20, the reaction was carried outin the same way.

After completion of the reaction, the results of gas chromatographicanalysis showed that 0.24 g. of acrylamide and 0.18 g. of ethylenecyanohydrin were obtained as the products.

EXAMPLE 23

Using in procedure described in Example 20, the reduction and reactionwere conducted using 10 g. of a silver catalyst on alumina carrier(3.5-4.0% Ag; Harshaw Chemical Co., U.S.A.) as the catalyst.

After completion of the reaction, the result of gas chromatographicanalysis showed that 0.57 g. of acrylamide and 0.27 g. of ethylenecyanohydrin were obtained as the products.

EXAMPLE 24

Except that 1.0 g. of silver powder was used as catalyst in theprocedure described in Example 20, the reduction and reaction werecarried out in the same way.

After the reaction, the results of gas chromatographic analysis showedthat 0.12 g. of acrylamide was obtained as the product together with avery small amount of an indeterminable substance.

EXAMPLE 25

Except that 1.0 g. of unreduced silver oxide Ag₂ O was used as thecatalyst in the procedure described in Example 20, the reaction wascarried out similarly as in the case of Example 20.

After the reaction, the results of gas chromatographic analysis showedthat 0.25 g. of acrylamide, and 0.31 g. of ethylene cyanohydrin wereobtained as the products together with a small amount of anindeterminable substance.

EXAMPLE 26

Except that 1.0 g. of gold oxide Au₂ O was used as the catalyst in theprocedure described in Example 20, the reduction and reaction werecarried out in the same way.

After the reaction, the results of gas chromatographic analysis showedthat 3.5 g. of acrylamide were obtained as the product together with avery small amount of an indeterminable substance.

EXAMPLE 27

Except that 1.0 g. of unreduced gold oxide Au₂ O was used as thecatalyst in the procedure described in Example 20, the reaction wascarried out at about 60° C. for 5 hours.

After the reaction, the results of gas chromatographic analysis showedthat 0.73 g. of acrylamide and 0.12 g. of ethylene cyanohydrin wereobtained as the products together with a very small amount of anindeterminable substance.

EXAMPLE 28

Using 1.0 g. of gold powder as the catalyst in the procedure describedin Example 20, the reduction was carried out and then the reaction wascarried out at about 60° C. for 5 hours.

After the reaction, the results of gas chromatographic analysis showedthat 0.52 g. of acrylamide and 0.13 g. of ethylene cyanohydrin wereobtained as the products.

EXAMPLE 29

Using as catalyst in the procedure described in Example 1 about 10 g. ofRaney copper (Kawaken Fine Chemical, CDT-60), 30.0 g. ofmethacrylonitrile and 13.3 g. of isopropanol were charged and reactedfor 2 hours at a reaction temperature of about 70° C. under agitation atatmospheric pressure.

After the reaction, the catalyst was filtered off and the filtrate wasevaporated to yield about 0.8 g. of a white crystalline product. Theproduct was dissolved in a mixture of diethyl ether and ethanol andrecrystallized therefrom to obtain a white crystalline product having amelting point of 109°-110° C. This product was identified asmethacrylamide, based upon the results of gas chromatographic analysis,elementary analysis, IR analysis and NMR analysis. Very small amounts ofacetone and an indeterminable substance were obtained as by-products.

EXAMPLE 30

In the procedure described in Example 29, 10 g. of Raney copper whichhad been developed and washed with water was further washed with ethanoland the composition of the reaction liquid was 30.0 g. ofmethacrylonitrile and 10.0 g. of ethanol. The liquid was reacted for 2hours at a reaction temperature of about 70° C.

After the reaction, the results of gas chromatographic analysis showedthat 0.6 g. of methacrylamide was obtained as the product. A smallamount of an indeterminable substance was obtained as by-product.

EXAMPLE 31

In the procedure described in Example 29, about 2 g. of Raney copperwhich had been developed and washed with water were subjected togetherwith a liquid mixture of 4.2 g. of methacrylonitrile and 36.0 g. ofwater to reaction for 2 hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 4.1 g. of methacrylamide were obtained as the product. Noby-product was found besides the product.

EXAMPLE 32

In the procedure described in Example 29, about 2 g. of Raney copperwhich had been developed and washed with water were used and a reactionliquid composed of 16.8 g. of methacrylonitrile, 18.0 g. of water and25.0 g. of dimethylformamide was reacted for 2 hours at a reactiontemperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 12.7 g. of methacrylamide were obtained as the product. Noby-product was found.

EXAMPLE 33

In the procedure described in Example 29, about 2 g. of Raney copperwhich had been developed and washed with water were used and a reactionliquid composed of 16.8 g. of methacrylonitrile, 18.0 g. of water and25.0 g. of isopropanol was reacted for 2 hours at a reaction temperatureof about 70° C.

After the reaction, the results of gas chromatographic analysis showedthat 13.6 g. of methacrylamide were obtained as the product. Noby-product was found.

EXAMPLE 34

In the precedure described in Example 29, about 2 g. of Ullmann copperwhich had been prepared by treating an aqueous solution of cupricnitrate with metallic zinc were used as the catalyst and a liquidmixture of 4.2 g. of methacrylonitrile and 36.0 g. of water was used asthe reaction liquid and reacted for 2 hours at a reaction temperature ofabout 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 2.8 g. of methacrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 35

In the procedure described in Example 29, a reduced copper catalyst wasused the catalyst. 125 Grams of cupric nitrate Cu(NO₃)₂ 3H₂ O weredissolved into 1500 ml. of water and the solution was warmed to 80° C. A20% aqueous solution of caustic potash was added dropwise to the abovesolution until the pH became 9-10 to obtain cupric hydroxide. Theresultant cupric hydroxide was washed well with warm water until thewash solution became neutral and then dried at 100° C. 10 Grams of theresulting cupric hydroxide were charged into a 100 ml. 4-necked flaskand reduced for 2 hours at 170° C. with hydrogen at a flow rate of 300ml./min. to prepare said catalyst. Into the flask containing saidreduced copper catalyst was poured a mixture of 4.2 g. ofmethacrylonitrile and 36.0 g. of water and the mixture was reacted for 2hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 2.9 g. of methacrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 36

In the procedure described in Example 29, a copper asbestos catalyst wasused as the catalyst. 15 Cubic centimeters of an aqueous solution ofcupric nitrate (4.2 g. as copper) were absorbed on 3 g. of asbestoswhich had been boiled with nitric acid, washed with water and thendried. The asbestos thus treated was added in portions to 50 cc of aboiling aqueous solution of caustic soda, filtered, washed with waterand then dried. The asbestos was then charged into a 100 ml. 4-neckedflask and reduced for 2 hours at 260° C. with hydrogen at a flow rate of50 ml./min. to prepare said copper asbestos catalyst. Into the flaskcontaining this copper asbestos catalyst was poured a liquid mixture of4.2 g. of methacrylonitrile and 36.0 g. of water and the mixture wasreacted for 2 hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.7 g. of methacrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 37

In the procedure described in Example 29, copper-chromium catalyst wasused as the catalyst. 10 Grams of copper-chromium oxide powderscontaining a small amount of manganese oxide (Nikki Kagaku,Copper-chromium catalyst N203) were charged into a 100 ml. 4-neckedflask, reduced for 5 hours at 200° C. with hydrogen at a flow rate of150 ml./min. and then cooled to room temperature while allowingintroduction of a hydrogen stream. Into the flask containing the reducedcopper-chromium was poured a liquid mixture of 4.2 g. ofmethacrylonitrile and 36.0 g. of water and the mixture was reacted for 2hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 2.4 g. of methacrylamide were obtained as the product.Substantially no by-products were found.

EXAMPLE 38

In the procedure described in Example 29, a copper-zinc catalyst wasused as the catalyst. 10 Grams of a cylindrically shaped materialcomprising copper oxide and zinc oxide (Nikki Kagaku, Copper-zinccatalyst N211) were crushed to power form, charged into a 100 ml.4-necked flask, reduced for 2 hours at 300° C. with hydrogen at a flowrate of 100 ml./min. and then cooled to room temperature while allowingthe introduction of a hydrogen stream. Into the flask containing thecopper-zinc catalyst was poured a liquid mixture of 4.2 g. ofmethacrylonitrile and 36.0 g. of water and the mixture was reacted for 2hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.4 g. of methacrylamide were obtained as the product.Substantially no by-products were scarcely found.

EXAMPLE 39

In the procedure described in Example 29, about 10 g. of Raney cobalt(Kawaken Fine Chemical, R-ODHT-60) which had been developed and washedwith water were used as the catalyst and a liquid mixture of 4.2 g. ofmethacrylonitrile and 36.0 g. of water was used as reaction liquid andreacted for 2 hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 0.9 g. of methacrylamide was obtained as the product together witha small amount of an indeterminable substance.

EXAMPLE 40

In the procedure described in Example 29, a cobalt catalyst with acarrier was used as the catalyst. 10 Grams of a reduction-stabilizedcobalt-diatomaceous earth catalyst (Chemetron Corp.) were placed in a 50ml. 2-necked, confined flask, heated and then reduced by passinghydrogen gas therethrough. In this case, the flow rate of hydrogen, thereduction temperature and the reaction time were 50 ml./min., 300° C.and 2 hours, respectively. After completion of the reduction, thecatalyst was cooled to room temperature while allowing introduction of ahydrogen stream. Introduction of the hydrogen stream was then stoppedand a liquid mixture of 4.2 g. of methacrylonitrile and 36.0 g. of waterwas poured onto the catalyst in such manner that the catalyst was notbrought into contact with air. The experiment was then conductedsimilarly to that of Example 1.

After the reaction, the analysis results showed that 0.8 g. ofmethacrylamide was obtained as the product together with a small amountof an indeterminable substance.

EXAMPLE 41

In the procedure described in Example 29, Raney nickel (Kawaken FineChemical, NDT-65) which had been developed and washed with water wasused as the catalyst and a liquid mixture of 4.2 g. of methacrylonitrileand 36.0 g. of water was used as the reaction liquid and reacted for 2hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.0 g. of methacrylamide and a small amount of an indeterminablesubstance were obtained as the products.

EXAMPLE 42

In the procedure described in Example 29, a nickel catalyst with acarrier was used as the catalyst. 10 Grams of a stabilizednickel-diatomaceous earth catalyst (Nikki Kagaku, N113; containing ascocatalyst a small amount of oxides of copper and chromium) were chargedinto a 50 ml. 2-necked, confined flask, heated and reduced by passinghydrogen gas therethrough. In that case, the flow rate of hydrogen, thereduction temperature and the reduction time were 100 ml./min., 200° C.and 2 hours, respectively. After completion of the reduction, thecatalyst was cooled to room temperature while allowing introduction of ahydrogen stream. Introduction of the hydrogen stream was then stoppedand a liquid mixture of 4.2 g. of methacrylonitrile and 36.0 g. of waterwas poured onto the catalyst in such manner that the catalyst was notbrought into contact with air. The experiment was then conductedsimilarly to the case of Example 1.

After the reaction, the results of analysis showed that 0.8 g, ofmethacrylamide was obtained as the product together with a small amountof an indeterminable substance.

EXAMPLE 43

In the procedure described in Example 29, a catalyst prepared byreducing 1.0 g. of 5% palladium carbon powder (Nihon Engerhalt) at 200°C. for 2 hours with hydrogen at a flow rate cf 50 ml./min. was used anda liquid mixture of 4.2 g. of methacrylonitrile and 36.0 g. of water wasused as reaction liquid and reacted for 5 hours at a reactiontemperature of about 80° C.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 1.1 g. of methacrylamide was obtained as the producttogether with a very small amount of an indeterminable substance.

EXAMPLE 44

In the procedure described in Example 29, a catalyst prepared byreducing 1.0 g. of 1% platinum carbon powder (Nihon Engerhalt) at 200°C. for 2 hours with hydrogen at a flow rate of 50 ml./min. was used asthe catalyst and a liquid mixture of 4.2 g. of methacrylonitrile and36.0 g. of water was used as the reaction liquid and reacted for 5 hoursat a reaction temperature of about 80° C.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 0.8 g. of methacrylamide was obtained as the product.No by-product was found.

EXAMPLE 45

In the procedure described in Example 29, 0.5 g. of palladium black wasused as the catalyst and a liquid mixture of 4.2 g. of methacrylonitrileand 36.0 g. of water was used as the reaction liquid and reacted for 5hours at a reaction temperature of about 80° C.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 1.2 g. of methacrylamide were obtained as the producttogether with a very small amount of an indeterminable substance.

EXAMPLE 46

In the procedure described in Example 29, 0.5 g. of platinum black wasused as the catalyst and a liquid mixture of 4.2 g. of methacrylonitrileand 36.0 g. of water was used as the reaction liquid and reacted for 5hours at a reaction temperature of about 80° C.

After the reaction, the catalyst was filtered off and the reactionliquid was subjected to gas chromatographic analysis, the result ofwhich showed that 1.0 g. of methacrylamide was obtained as the product.No by-product was found.

EXAMPLE 47

In the procedure described in Example 29, 10 g. of a silver oxide onalumina carrier (1% Ag₂ O; Toyo CCI) were reduced for 2 hours at 200° C.with hydrogen at a flow rate of 50 ml./min. to prepare a catalyst and aliquid mixture of 4.2 g. of methacrylonitrile and 36.0 g. of water wassubjected together with the catalyst to reaction for about 2 hours at areaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.3 g. of methacrylamide were obtained as the product. Noby-product was found.

EXAMPLE 48

In the procedure described in Example 29, 10 g. of unreduced silveroxide on alumina carrier were directly used as the catalyst and a liquidmixture of 4.2 g. of methacrylonitrile and 36.0 g. of water was reactedin the presence of the catalyst for about 2 hours at a reactiontemperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.1 g. of methacrylamide was obtained as the product together witha very small amount of an indeterminable substance.

EXAMPLE 49

In the procedure described in Example 29, a catalyst prepared byreducing 1.0 g. of gold oxide Au₂ O at 200° C. for 2 hours with hydrogenat a flow rate of 50 ml./min. was subjected together with a liquidmixture of 4.2 g. of methacrylonitrile and 36.0 g. of water to reactionfor 2 hours at about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 2.1 g. of methacrylamide were obtained as the product. Noby-product was found.

EXAMPLE 50

In the procedure described in Example 29, 1.0 g. of unreduced gold oxideAu₂ O was directly used as the catalyst and a liquid mixture of 4.2 g.of methacrylonitrile and 36.0 g. of water was reacted in the presence ofthe catalyst for about 2 hours at a reaction temperature of about 80° C.

After the reaction, the results of gas chromatographic analysis showedthat 1.7 g. of methacrylamide were obtained as the product together witha very small amount of an indeterminable substance.

What is claimed is:
 1. In the process for converting an aliphaticnitrile selection from the group consisting of acrylonitrile andmethacrylonitrile to the corresponding amide by reacting the aliphaticnitrile with water in the presence of a heterogeneous catalyst, theimprovement comprising using a catalytic amount of a catalyst consistingessentially of Raney copper, which is protected from contact withoxygen, the reaction being run at a temperature of about 25° to 200° C.,the reaction being carried out in a suspended state, and the reactionbeing carried out under a pressure which is effective for said reactionto occur, with the proviso that said pressure does not exceed 300kg/cm².
 2. The process as claimed in claim 1 wherein the amount of waterused is 0.01 to 100 moles per mole of said aliphatic nitrile.